Core-shell structure supported tungsten composite catalyst and preparation method and use thereof

Abstract

The present invention discloses a core-shell structure supported tungsten composite catalyst and a preparation method and use thereof. Most of the existing synthesis methods of the main ring of quinolone drugs have the defects of many synthesis steps, cumbersome operation, large amount of three wastes, higher costs and the like. The present invention prepares a magnetic separable core-shell supported tungsten composite catalyst, WO3/SiO2/Fe3O4, by preparing Fe3O4 colloid and SiO2/Fe3O4 composite nano-particles. This magnetic separable core-shell supported tungsten composite catalyst, WO3/SiO2/Fe3O4, is used to catalyze and synthesize quinolone compounds. The present invention provides an efficient preparation method of quinolone compounds using a catalyst which can be recovered by magnetic separation and recycled. The catalyst prepared by the present invention can be reused in the preparation of quinolone compounds and still retains the original activity without deactivation, which not only greatly improves the production efficiency, but also reduces the environmental pollution.

The invention claimed is: 
     
       1. A preparation method of a core-shell structure supported tungsten composite catalyst, comprising the steps of:
 step 1), adding a reducing agent and a base into an aqueous solution of iron compound, heating to 50-80° C. and stirring to obtain Fe 3 O 4  colloid; 
 step 2), adding the Fe 3 O 4  colloid obtained in the step 1), tetraethyl orthosilicate and a hydrolysis catalyst into an appropriate amount of dispersion solvent and allowing to react for 4-8 hours to obtain SiO 2 /Fe 3 O 4  composite nano-particles; and 
 step 3), adding the SiO 2 /Fe 3 O 4  composite nano-particles obtained in step 2) into an aqueous solution of ammonium metatungstate, stirring for 8-14 hours and drying at 90-150° C. to obtain a first solid, which is calcined at 450-650° C. for 1-6 hours to obtain a magnetic separable core-shell structure supported tungsten composite catalyst, WO 3 /SiO 2 /Fe 3 O 4 ; 
 wherein the molar ratio of the iron compound: tetraethyl orthosilicate:ammonium metatungstate=1:1-10:0.1-1; 
 and wherein the iron compound is FeCl 3 , FeCl 3 .6H 2 O or ferric triacetylacetonate; the reducing agent is Na 2 SO 3 , ascorbic acid or hydrazine hydrate; and the base is aqueous ammonia, sodium hydroxide or sodium acetate. 
 
     
     
       2. The preparation method according to  claim 1 , wherein the iron compound is FeCl 3 . 
     
     
       3. The preparation method according to  claim 1 , wherein the reducing agent is Na 2 SO 3 . 
     
     
       4. The preparation method according to  claim 1 , wherein the base is aqueous ammonia. 
     
     
       5. The preparation method according to  claim 1 , wherein in step 1), after heating, polyvinylpyrrolidone is added as a surfactant, the mixture is stirred continuously, then centrifuged and washed with water, and finally dispersed, and water is then removed to obtain Fe 3 O 4  colloid. 
     
     
       6. The preparation method according to  claim 1 , wherein in step 2), the dispersion solvent is ethanol, and the hydrolysis catalyst is aqueous ammonia. 
     
     
       7. The preparation method according to  claim 1 , wherein in step 3), the first solid is first ground through a 120-mesh standard sieve and then calcined at 450-650° C. for 1-6 hours. 
     
     
       8. A magnetic separable core-shell supported tungsten composite catalyst, WO 3 /SiO 2 /Fe 3 O 4 , prepared by the preparation method of  claim 1 . 
     
     
       9. A magnetic separable core-shell supported tungsten composite catalyst, WO 3 /SiO 2 /Fe 3 O 4 , prepared by the preparation method of  claim 2 . 
     
     
       10. A magnetic separable core-shell supported tungsten composite catalyst, WO 3 /SiO 2 /Fe 3 O 4 , prepared by the preparation method of  claim 3 . 
     
     
       11. A magnetic separable core-shell supported tungsten composite catalyst, WO 3 /SiO 2 /Fe 3 O 4 , prepared by the preparation method of  claim 4 . 
     
     
       12. Use of the magnetic separable core-shell structure supported tungsten composite catalyst, WO 3 /SiO 2 /Fe 3 O 4 , of  claim 8  in the synthesis of quinolone compounds, wherein the reaction steps are as follows:
 step 1), stirring and mixing ethyl formylacetate sodium salt, a non-polar organic solvent and the WO 3 /SiO 2 /Fe 3 O 4  catalyst, introducing an amine compound, adding 2,4-dichloro-5-fluorobenzoyl chloride and allowing to react for 0.5-3 hours; 
 step 2), following step 1), adding a primary amine dropwise while introducing CO 2  to control the reaction pressure at 1-5 atmospheres and allowing to react for 0.5-3 hours; 
 step 3), following step 2), adding an alkali metal hydroxide and a non-polar organic solvent, stirring and raising the temperature to 100° C. for half an hour, filtering to recover the catalyst and increasing the pressure to recover the non-polar organic solvent; and 
 step 4), following step 3), adding an appropriate amount of water, raising the temperature to 100° C., adding hydrochloric acid dropwise to adjust the power of hydrogen to control the pH range at 4.8-6.5, precipitating crystals, followed by centrifugation and drying, and obtaining quinolone compounds; 
 wherein the non-polar organic solvent is toluene, xylene or a mixture of the former two; the amine compound is dimethylamine, diethylamine or dicyclohexylamine; the primary amine is cyclopropylamine or S-propylene glycol amine; and the alkali metal hydroxide is sodium hydroxide, lithium hydroxide or potassium hydroxide. 
 
     
     
       13. Use of the magnetic separable core-shell structure supported tungsten composite catalyst, WO 3 /SiO 2 /Fe 3 O 4 , of  claim 9  in the synthesis of quinolone compounds, wherein the reaction steps are as follows:
 step 1), stirring and mixing ethyl formylacetate sodium salt, a non-polar organic solvent and the WO 3 /SiO 2 /Fe 3 O 4  catalyst, introducing an amine compound, adding 2,4-dichloro-5-fluorobenzoyl chloride and allowing to react for 0.5-3 hours; 
 step 2), following step 1), adding a primary amine dropwise while introducing CO 2  to control the reaction pressure at 1-5 atmospheres and allowing to react for 0.5-3 hours; 
 step 3), following step 2), adding an alkali metal hydroxide and a non-polar organic solvent, stirring and raising the temperature to 100° C. for half an hour, filtering to recover the catalyst and increasing the pressure to recover the non-polar organic solvent; and 
 step 4), following step 3), adding an appropriate amount of water, raising the temperature to 100° C., adding hydrochloric acid dropwise to adjust the power of hydrogen to control the pH range at 4.8-6.5, precipitating crystals, followed by centrifugation and drying, and obtaining quinolone compounds; 
 wherein the non-polar organic solvent is toluene, xylene or a mixture of the former two; the amine compound is dimethylamine, diethylamine or dicyclohexylamine; the primary amine is cyclopropylamine or S-propylene glycol amine; and the alkali metal hydroxide is sodium hydroxide, lithium hydroxide or potassium hydroxide. 
 
     
     
       14. Use of the magnetic separable core-shell structure supported tungsten composite catalyst, WO 3 /SiO 2 /Fe 3 O 4 , of  claim 10  in the synthesis of quinolone compounds, wherein the reaction steps are as follows:
 step 1), stirring and mixing ethyl formylacetate sodium salt, a non-polar organic solvent and the WO 3 /SiO 2 /Fe 3 O 4  catalyst, introducing an amine compound, adding 2,4-dichloro-5-fluorobenzoyl chloride and allowing to react for 0.5-3 hours; 
 step 2), following step 1), adding a primary amine dropwise while introducing CO 2  to control the reaction pressure at 1-5 atmospheres and allowing to react for 0.5-3 hours; 
 step 3), following step 2), adding an alkali metal hydroxide and a non-polar organic solvent, stirring and raising the temperature to 100° C. for half an hour, filtering to recover the catalyst and increasing the pressure to recover the non-polar organic solvent; and 
 step 4), following step 3), adding an appropriate amount of water, raising the temperature to 100° C., adding hydrochloric acid dropwise to adjust the power of hydrogen to control the pH range at 4.8-6.5, precipitating crystals, followed by centrifugation and drying, and obtaining quinolone compounds; 
 wherein the non-polar organic solvent is toluene, xylene or a mixture of the former two; the amine compound is dimethylamine, diethylamine or dicyclohexylamine; the primary amine is cyclopropylamine or S-propylene glycol amine; and the alkali metal hydroxide is sodium hydroxide, lithium hydroxide or potassium hydroxide. 
 
     
     
       15. Use of the magnetic separable core-shell structure supported tungsten composite catalyst, WO 3 /SiO 2 /Fe 3 O 4 , of  claim 11  in the synthesis of quinolone compounds, wherein the reaction steps are as follows:
 step 1), stirring and mixing ethyl formylacetate sodium salt, a non-polar organic solvent and the WO 3 /SiO 2 /Fe 3 O 4  catalyst, introducing an amine compound, adding 2,4-dichloro-5-fluorobenzoyl chloride and allowing to react for 0.5-3 hours; 
 step 2), following step 1), adding a primary amine dropwise while introducing CO 2  to control the reaction pressure at 1-5 atmospheres and allowing to react for 0.5-3 hours; 
 step 3), following step 2), adding an alkali metal hydroxide and a non-polar organic solvent, stirring and raising the temperature to 100° C. for half an hour, filtering to recover the catalyst and increasing the pressure to recover the non-polar organic solvent; and 
 step 4), following step 3), adding an appropriate amount of water, raising the temperature to 100° C., adding hydrochloric acid dropwise to adjust the power of hydrogen to control the pH range at 4.8-6.5, precipitating crystals, followed by centrifugation and drying, and obtaining quinolone compounds; 
 wherein the non-polar organic solvent is toluene, xylene or a mixture of the former two; the amine compound is dimethylamine, diethylamine or dicyclohexylamine; the primary amine is cyclopropylamine or S-propylene glycol amine; and the alkali metal hydroxide is sodium hydroxide, lithium hydroxide or potassium hydroxide. 
 
     
     
       16. The use according to  claim 12 , wherein the non-polar organic solvent is toluene, the amine compound is dimethylamine, the primary amine is cyclopropylamine, and the alkali metal hydroxide is sodium hydroxide. 
     
     
       17. The use according to  claim 13 , wherein the non-polar organic solvent is toluene, the amine compound is dimethylamine, the primary amine is cyclopropylamine, and the alkali metal hydroxide is sodium hydroxide. 
     
     
       18. The use according to  claim 14 , wherein the non-polar organic solvent is toluene, the amine compound is dimethylamine, the primary amine is cyclopropylamine, and the alkali metal hydroxide is sodium hydroxide. 
     
     
       19. The use according to  claim 15 , wherein the non-polar organic solvent is toluene, the amine compound is dimethylamine, the primary amine is cyclopropylamine, and the alkali metal hydroxide is sodium hydroxide.